mineral

Quartz Geode

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale. Color: White, clear, with minor yellowish or brownish iron-oxide staining. Luster: Vitreous (glassy) to greasy. Crystal structure: Trigonal. Cleavage: None, exhibits conchoidal fracture. Specific gravity: 2.65

Hardness: 7 on Mohs scale
Luster: Vitreous (glassy) to greasy

Identified July 29, 2026More mineral →

Explore Quartz Geode in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed in hollow cavities in sedimentary or volcanic rocks where silica-rich groundwater or hydrothermal fluids slowly precipitate quartz crystals inward from the cavity walls over long periods.

Uses & applications

Used in decorative items, mineral collections, jewelry making, and industrial applications requiring pure silica.

Geological facts

Geodes appear as ordinary, somewhat bumpy rocks on the outside, but cracking them open reveals a sparkling interior of quartz or other mineral crystals. They are found worldwide in various geological formations.

Field identification & locations

Easily identified by its hard quartz crystals lining a hollow or central cavity, and its lack of cleavage with a conchoidal fracture. Found in regions with significant limestone, volcanic ash beds, or hydrothermal activity.